Deflectable catheter steering and locking system

ABSTRACT

A deflectable catheter includes a catheter shaft having a deflectable distal tip. A support member is coupled around a proximal portion of the catheter shaft, and the support member includes a first brake portion extending along at least a portion of the support member. A handle is coupled around the support member. The deflectable catheter includes a carriage moveably coupled along the handle, and the carriage includes a second brake portion sized and shaped to engage with at least a portion of the first brake portion. A flexible element is coupled between the deflectable distal tip and the carriage. A biasing device is adapted to bias the second brake portion into engagement with the first brake portion.

TECHNICAL FIELD

Deflectable catheters and in particular to steering and locking systemsfor retaining a desired orientation of a deflectable catheter distaltip.

BACKGROUND

Many current deflectable catheters include some form of locking deviceconfigured to retain a deflected portion of the catheter in thedeflected orientation. In some examples, locking mechanisms anddeflection mechanisms are separate from each other, thereby requiringdual controls and complicating use and manufacture of the catheter. Forinstance, the grip on the handle must be repeatedly readjusted to switchbetween actuating the locking mechanism and the deflection mechanism.Further, space in the handle must be set aside for separate locking anddeflection mechanisms, thereby requiring tightly packed and complexhandles or larger handles to accommodate the mechanisms.

Other examples of catheters include ratcheting teeth that preventmovement of a deflection control actuator in one direction whilepermitting movement of the actuator in another direction andcorresponding continued deflection of the catheter. Ratchetingengagement of the actuator with the handle permits undesired deflectionof the catheter, for example, where the catheter engages againstvasculature during longitudinal movement of the catheter.

In still other examples, pull wires extend from the deflectable tip of acatheter shaft to the deflection control actuator, and the pull wiresare not constrained from lateral movement within the handle. The pullwire may only be tensioned in one direction in this configurationthereby only allowing deflection in a single direction. Compression ofthe pull wire in another direction will buckle the wire and therebysubstantially prevent active deflection of the catheter with thedeflection control actuator. Straightening of the catheter in adirection opposed to that granted by tensioning the pull wire is therebyaccomplished with the natural elasticity of the catheter distal tip. Thedeflected shaft exerts a passive pulling force on the pull wire thatstraightens the catheter without active control through the deflectioncontrol actuator. Further, the elasticity of the catheter onlystraightens the catheter and does not deflect the catheter in an opposeddirection.

Additionally, in yet other examples, deflectable catheters includelocking surfaces formed with the handle that substantially preventadjustment of a range of travel for the deflection control actuator. Forinstance, the locking surfaces are formed along an interior surface ofthe handle. Changing the range of travel for the actuator requiresredesigning the handle with a differently positioned locking surface.Multiple handle designs are therefore needed to accommodate desiredranges of travel for different catheter sizes, ranges of deflection andthe like.

What is needed is a deflectable catheter that overcomes the shortcomingsof previous designs. What is further needed is an easy to usedeflectable catheter with locking and deflection functions that is notlimited to passive deflection to straighten the catheter.

SUMMARY

A deflectable catheter including a catheter shaft having a deflectabledistal tip. A support member is coupled around a proximal portion of thecatheter shaft, and the support member includes a first brake portionextending along at least a portion of the support member. Thedeflectable catheter further includes a handle coupled around thesupport member. A carriage is moveably coupled along the handle, and thecarriage includes a second brake portion sized and shaped to engage withat least a portion of the first brake portion and substantially preventmovement of the carriage relative to the handle. A flexible element iscoupled between the deflectable distal tip and the carriage. A biasingdevice is coupled between the carriage and the handle, and the biasingdevice is adapted to bias the second brake portion into engagement withthe first brake portion. In one option, the first brake portion is arack and the second brake portion is at least one projection sized andshaped to engage with the rack.

Several options for the deflectable catheter follow. In one option, thecatheter shaft includes a flexible element guide and the flexibleelement extends outside of the catheter shaft at the flexible elementguide. The support member includes, in another option, a proximal stopproximal to the rack. Optionally, the carriage has a range of travelbetween the flexible element guide and the proximal stop, and thesupport member is coupled around a predetermined location of thecatheter shaft to define the range of travel.

In another option, the carriage includes an actuator adapted to move atleast a portion of the carriage between a first position where the atleast one projection is engaged with the rack and a second positionwhere the at least one projection is disengaged with the rack. In yetanother option, the deflectable catheter includes a carriage guideslidably coupled with the carriage, and the carriage guide is sized andshaped to permit lateral movement of a portion of the carriage andsubstantially prevent lateral movement of a second portion of thecarriage. The carriage guide is sized and shaped to permit longitudinalmovement of the carriage along the handle.

A method for making a deflectable catheter includes coupling a flexibleelement to a deflectable distal tip of a catheter shaft. A supportmember is coupled around a proximal portion of the catheter shaft, andthe support member includes a first brake portion extending along atleast a portion of the support member. A handle is coupled around thesupport member. In one option, the handle is coupled around a hemostasisvalve, and the hemostasis valve is in communication with a deliverylumen of the catheter shaft. The method further includes moveablycoupling a carriage assembly with the handle. The carriage assemblyincludes a carriage having second brake portion sized and shaped toengage with at least a portion of the first brake portion. A flexibleelement is coupled with the carriage assembly. A biasing device iscoupled between the carriage assembly and the handle and moveablycoupled along the handle. The biasing device is adapted to bias thesecond brake portion into engagement with the first brake portion.Optionally, the method includes coupling an actuator with the carriage.The actuator is adapted to move the carriage between a first positionwhere the second brake portion is engaged with the first brake portionand a second position where the second brake portion is disengaged withthe first brake portion.

Several options for the method follow. In one option, a retainer isslidably coupled with the carriage, and the flexible element is coupledwith the retainer. The retainer is sized and shaped to move with thecarriage longitudinally along the handle, and the retainer is sized andshaped to remain substantially laterally static relative to the flexibleelement, for instance when the carriage is moved laterally. Optionally,the method includes slidably coupling a carriage guide with the carriageassembly, and the carriage guide is sized and shaped to permit lateralmovement of the carriage relative to the flexible element andsubstantially prevent lateral movement of the retainer. The carriageguide is sized and shaped to permit movement of the carriage assemblylongitudinally along the handle.

The above described deflectable catheter provides a steering and lockingsystem capable of locking the deflectable distal tip in a desireddeflected position. The carriage and retainer cooperate with the supportmember to longitudinally move the flexible element to deflect the distaltip and lock the distal tip in a desired deflected position. Thesteering and locking system substantially prevents movement of thecarriage proximally or distally, thereby substantially preventingfurther undesired deflection of the catheter or straightening when thecarriage is in the locked position. Optionally, the steering and lockingsystem automatically locks the catheter in a desired orientation byreleasing the actuator. In one option, the carriage includes the secondbrake portion having, for instance, multiple projections that provide astrong locking force between the carriage and the first brake portion(e.g., rack, high friction surface and the like) of the support memberto securely retain the distal tip of the catheter in a deflectedorientation.

As described above, the carriage assembly including the carriage andretainer are operated to deflect the distal tip and lock the distal tipin a desired deflected position. The carriage assembly therebyconsolidates the deflection system with the locking system into thesingle steering and locking system to simplify use of the catheter. Inanother option, a single actuator is used to control both the deflectionand locking of the deflectable catheter. Additional controls and thelike are unnecessary. Further, combining the deflection and lockingfeatures decreases labor and manufacturing costs. Moreover, in anotheroption, the catheter handle includes a hemostasis valve and/or flushport therein to further simplify use of the deflectable catheter.

Additionally, the support member provides a brake portion for lockingthe carriage in place and is a structural support to the catheter shaftduring deflection and traversing of the vasculature. Moreover, thesupport member is coupled along the catheter shaft at a predeterminedlocation to provide a range of travel for the carriage, and thereby arange of deflection of the distal tip. The space between the proximalstop of the support member and the flexible element guide along thecatheter shaft defines the range of travel and corresponding range ofdeflection for the distal tip. Coupling the support member distallytoward the flexible element guide provides a short range of travel(e.g., for thin walled catheters). Coupling the support memberproximally away from the flexible element guide provides a longer rangeof travel (e.g., for thicker catheters, greater deflection ranges, andthe like). Further, coupling the support member at the predeterminedlocation also establishes a neutral position for the carriage where thedeflectable distal tip assumes an undeflected orientation. The supportmember is coupled along the catheter body at a variety of locations todefine a corresponding variety of ranges of travel. In yet anotheroption, the support member is coupled with a standard handle sized andshaped to receive the support member. A single handle is thereby usedwith the same support member no matter what the range of travel is ofthe carriage assembly thereby decreasing labor and manufacturing costs.

Further, the retainer and tube assembly substantially prevent bucklingof the flexible element thereby allowing tension and compression loadingof the flexible element. Because the flexible element is constrainedfrom moving laterally between the retainer and the deflectable distaltip the element is loadable in tension and compression to providebi-directional deflection of the distal tip. In another option, loadingthe flexible element in compression permits active straightening of thedeflected catheter thereby providing active control for deflection andstraightening with the carriage assembly (i.e., the natural catheterelasticity does not unpredictably control straightening of the distaltip). The carriage guide, in yet another option, facilitateslongitudinal movement of the carriage and the retainer while holding theretainer in a substantially laterally static position with respect tothe flexible element. The carriage guide thereby ensures the retainercooperates with the tube assembly to keep the flexible element laterallystatic, while permitting longitudinal movement of the carriage assemblyfor deflection of the distal tip. Additionally, the carriage guidepermits lateral movement of the carriage to engage and disengage thesecond brake portion of the carriage with the first brake portion of thesupport member.

These and other embodiments, aspects, advantages, and features of thepresent invention will be set forth in part in the description whichfollows, and in part will become apparent to those skilled in the art byreference to the following description of the invention and referenceddrawings or by practice of the invention. The aspects, advantages, andfeatures of the invention are realized and attained by means of theinstrumentalities, procedures, and combinations particularly pointed outin the appended claims and their equivalents.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a perspective view of one example of a deflectable catheterin a first deflected orientation.

FIG. 1B is a perspective view of the deflectable catheter in a neutralorientation.

FIG. 1C is a perspective view of the deflectable catheter in a seconddeflected orientation.

FIG. 2 is a partial sectional view of one example of the deflectabledistal tip.

FIG. 3 is a perspective view of one example of the catheter handleassembly including a flush port.

FIG. 4 is a cross section of the catheter handle assembly taken alongline 4-4 of FIG. 3.

FIG. 5 is a perspective view of one example of the carriage.

FIG. 6 is a perspective view of one example of the steering and lockingsystem including the carriage assembly and the support member.

FIG. 7 is a perspective view of another example of the steering andlocking system including the carriage guide member.

FIG. 8 is a perspective view of another example of the carriage assemblyand a portion of the tube assembly.

FIG. 9 is a perspective view of one example of the tube assembly.

FIG. 10 is a detailed perspective view of a portion of a retainer andthe tube assembly.

FIG. 11A is a perspective view of yet another example of the steeringand locking system including the carriage assembly having a first rangeof travel between the flexible element guide and the proximal stop.

FIG. 11B is a perspective view of still another example of the steeringand locking system including the carriage assembly having a second rangeof travel between the flexible element guide and the proximal stop.

FIG. 12 is a block diagram showing one example of a method for making adeflectable catheter.

DESCRIPTION OF THE EMBODIMENTS

In the following detailed description, reference is made to theaccompanying drawings which form a part hereof, and in which is shown byway of illustration specific embodiments in which the invention may bepracticed. These embodiments are described in sufficient detail toenable those skilled in the art to practice the invention, and it is tobe understood that other embodiments may be utilized and that structuralchanges may be made without departing from the scope of the presentinvention. Therefore, the following detailed description is not to betaken in a limiting sense, and the scope of the present invention isdefined by the appended claims and their equivalents.

FIGS. 1A, 1B and 1C illustrate a deflectable catheter assembly 100,where FIG. 1A illustrates the deflectable catheter assembly 100 in onearticulated position, and FIG. 1C illustrates the catheter assembly 100in another articulated orientation. FIG. 1B illustrates the deflectablecatheter assembly 100 in an unarticulated neutral position. Thedeflectable catheter assembly 100 includes a catheter body 110 and ahandle assembly 150 that houses a steering and locking mechanism fordeflection of the catheter body 110. The handle assembly 150 allows forthe selectable deflection of a distal end of the catheter body 110 intoany number of disparate orientations, as further described below.

The catheter body 110 comprises an elongate tubular construction that isflexible yet substantially non-compressible along its length. Thedeflectable catheter body 110 extends from a proximal end 102 to adeflectable distal tip 104, where the deflectable distal tip 104 isadapted to be disposed within a patient. At the proximal end 102, thephysician controls the deflection of the deflectable catheter body 110with the handle assembly 150 containing the steering and lockingmechanism and a flexible element, such as a push-pull wire, as furtherdescribed below. The deflectable distal tip 104 is deflected to traversevarious branch vessels with the catheter assembly 100 (FIGS. 1A and 1C).

FIG. 2 illustrates a partial cut-away view of the deflectable distal tip104 shown in FIGS. 1A, B, C. The catheter body 110 includes a deliverylumen 105, in one option. The delivery lumen 105 extends through thecatheter body 110 between the proximal end 102 and the deflectabledistal tip 104. The delivery lumen 105 is sized and shaped to receive,for example, instruments, fluids, media and the like. A flexible element120, such as a push-pull wire, extends through the cathether body 110and into the deflectable distal tip 104. The flexible element 120, inanother option, extends through the catheter sidewall 124 surroundingthe delivery lumen 105. The deflectable distal tip 104 includes ananchor 122 coupled with the flexible element 120. The anchor 122 iscoupled with the catheter body 110 at the deflectable distal tip 104 andtransmits pushing and pulling forces from the flexible element 120 tothe deflectable distal tip to cause deflection of the distal tip. In oneoption, the anchor 122 is encapsulated within the catheter sidewall 124with an encapsulant, such as a plastic. Optionally, the encapsulantincludes, but is not limited to PEBAX a registered trademark of theAtofina Corporation. It should be noted that the flexible element 120can be secured to the deflectable distal tip 104 of the catheter body110 by other means such as coupling with a marker band 126. The markerband 126 is constructed with a material that is visible with an imagingprocedure, such as fluoroscopy. In another option, the flexible element120 is coupled to the marker band 126 and/or anchor 122 by crimping,welding, soldering, brazing, interference fitting and the like. In oneoption, the catheter body 110 includes a stiffening member embeddedtherein, such as a braided stainless steel member 111. The stiffeningmember facilitates rotation of the deflectable distal tip 104 from theproximal end 102, and also assists in preventing the catheter body 110from collapsing.

FIG. 3 shows one example of the handle assembly 150 with a flush port300 coupled to the assembly 150. The handle assembly 150 is coupled withthe proximal end 102 of the catheter body 110. In one option, the handleassembly 150 includes a strain relief fitting 302 surrounding at least aportion of the proximal end 102 and coupled with the handle assembly150. The strain relief fitting 302 extends toward the deflectable distaltip 104 to provide support to the proximal end 102 of the catheter body110. The strain relief fitting 302, in another option, has apredetermined stiffness that provides support to the proximal end 102 tominimize kinking of the catheter body 110 adjacent to the handleassembly 150. In yet another option, the strain relief fitting 302 isconstructed with plastics, metals and the like. For instance, the strainrelief fitting 302 includes SANTOPRENE a registered trademark ofAdvanced Elastomer Systems, L.P. The handle assembly 150 and thecomponents therein are constructed with, but not limited to, plastics,metals and the like. In one example, the handle assembly 150 isconstructed with a composite such as a glass fiber filled polycarbonate.Optionally, the handle assembly 150 and its components are formed bymolding, machining, extrusion, pultrusion and the like. In yet anotheroption, the handle assembly 150 is formed with a plurality of processes(e.g., molding and machining).

As shown in FIG. 3, the handle assembly 150 includes an actuator 304,such as a slide. In another option, the actuator 304 includes, but isnot limited to, a button, wheel, knob and the like. The actuator 304, inyet another option, is constructed with a plastic, such aspolycarbonate. The actuator 304 is part of a steering and locking system(described below) and is operated to deflect the deflectable distal tip104 (FIGS. 1A, B, C and 2). Optionally, the actuator 304 is movedproximally and distally along the handle assembly 150 (e.g., with thumbor finger pressure) to actively control deflection of the distal tip104. As further described below, the actuator 304 is moveable laterallywith respect to the handle assembly 150 (e.g., toward and away from thehandle assembly) to lock the deflectable distal tip 104 in a desiredorientation.

In another option, the handle assembly 150 includes an access point,such as a hemostasis valve 306. The hemostasis valve 306, optionally, ispositioned at the proximal end 308 of the handle assembly 150 andprovides access to the delivery lumen 105 (FIG. 2). The hemostasis valve306 allows for insertion of instruments and devices having a variety ofsizes into the delivery lumen 105. The hemostasis valve 306substantially prevents blood loss out of the delivery lumen 105 and theentrance of air and other gases into the delivery lumen 105 duringinsertion and extraction of the instruments and devices. The hemostasisvalve 306 is constructed with, but not limited to, plastics, metals andthe like. In one example, the hemostasis valve 306 includes glass fiberfilled nylon and has a flexible silicone membrane to permit passage ofinstruments and devices. In yet another option, the handle assembly 150includes a luer fitting sized and shaped to couple with a variety ofcomponents (e.g., instruments and the like) that have a mating luerfitting.

In yet another option, the flush port assembly 300 is in communicationwith the delivery lumen 105 (FIG. 2) by a tube 312 coupled therebetween.The flush port assembly 300 includes a nozzle 310 sized and shaped toreceive a fluid, for instance saline. Fluids are injected into thedelivery lumen 105 through the flush port assembly 300. In one example,saline is injected through the flush port assembly 300 to flush air outof the delivery lumen 105. In another example, fluids, such as contrastmedia, medications and the like are injected through the flush portassembly 300 and fed down the delivery lumen 105 to a targeted area(e.g., within a vessel).

FIG. 4 is a cross sectional view of the handle assembly 150 taken alongline 4-4 of FIG. 3 and showing a steering and locking system 401. Theproximal end 102 of the catheter body 110 extends through at least aportion of the handle assembly 150. In one option, the proximal end 102is in communication with the hemostasis valve 306 described above. Asshown in FIG. 4, the proximal end 102 of the catheter body 110 iscoupled with the handle assembly 150 by a support member 400, in anotheroption. The support member 400 extends around at least a portion of theproximal end 102 and secures the catheter body 110 to the handleassembly 150. The proximal end 102 is held within the support member 400and substantially constrained from moving laterally or longitudinallyand the support member 400 thereby provides a strong structural couplingbetween the catheter body 110 and the handle assembly 150. Optionally,the support member 400 clamps around the proximal end 102 to secure thecatheter body 110 to the handle assembly 150. In yet another option,adhesives, welds, fasteners and like are used to couple the catheterbody 110 to the support member 400 and the handle assembly 150. Thesupport member 400 is positioned near the center of the handle assembly150 and retained therein by ribs 402 extending between the supportmember 400 and the handle assembly 150. The ribs 402, in still anotheroption, extend around at least a portion of the support member 400. Theribs 402 extend into recesses (described below in FIG. 6), in an option,of the support member 400 to substantially prevent movement of thesupport member 400 and catheter body relative to the handle assembly150. The ribs 402 and the support member 400 cooperate to align theproximal end 102 of the catheter body 110 with the hemostasis valve 306and the strain relief fitting 302 (described above). The support member400 is retained in the handle assembly 150, in still another option,with adhesives, welds, fasteners and the like. Optionally, the supportmember 400 is constructed with plastics, metals and the like. Thesupport member 400 includes polycarbonate, in one example.

As described above, the flexible element 120 extends from thedeflectable distal tip (FIG. 2) through the catheter body 110. As shownin FIG. 4, the flexible element 120 exits the catheter body 110 at asidewall exit 403 of the proximal end 102 and is coupled with a carriageassembly 406 moveably coupled along the handle assembly 150. Theflexible element 120 is coupled with the carriage assembly 406 with aretaining pin 408 (e.g., a stainless steel retaining pin), in oneoption. In another option, the flexible element 120 is coupled with thecarriage assembly 406 with, but not limited to, welds, set screws,clamps, adhesives and the like. Moving the carriage assembly 406 of thesteering and locking system 401 longitudinally along the handle assembly150 moves the flexible element 120 coupled with the assembly 406.Movement of the flexible element 120 is transmitted to the deflectabledistal tip 104 (FIG. 2) and deflects the distal tip 104 into a varietyof orientations, including for instance the orientations shown in FIGS.1A, C. In yet another option, the movement of the carriage assembly 406and corresponding movement of the flexible element 120 straightens thedeflectable distal tip 104 from a deflected orientation (FIGS. 1A, C)into a substantially straight neutral position, as shown in FIG. 1B.

The carriage assembly 406 includes a carriage 410 sized and shaped tomove laterally (e.g., perpendicular to the flexible element 120 and thecatheter body proximal end 102) to lock the carriage assembly 406 andthe flexible element 120 coupled thereto in a desired position withrespect to the support member 400 and allow retention of the deflectabledistal tip 104 in a desired orientation. The carriage 410 is constructedwith, but not limited to, plastics, metals and the like. In one example,the carriage 410 includes a blend of polycarbonate and acrylonitrilebutadiene styrene (ABS). As shown in FIG. 4, the carriage 410 of thesteering and locking system 401 includes a brake portion 412. The brakeportion 412, in one option, includes at least one projection 414.Referring now to FIG. 5, in the example shown, multiple projections 414are provided for enhanced locking between the support member 400 (FIG.4) and the carriage 410 (further described below). Optionally, the brakeportion 412 extends along an interior surface 500 of the carriage 410,and the projections 414 extend away from the interior surface 500 towardthe support member 400.

Referring again to FIG. 4, the steering and locking system 401 includesa second brake portion 416 extending along at least a portion of thesupport member 400. The second brake portion 416 is sized and shaped toengage with the brake portion 412 (e.g., projections 414) andsubstantially prevent movement of the carriage assembly 406 along thehandle assembly 150. In one option, the support member 400 includes arack 418 sized and shaped to mate and interlock with the projections 414of the carriage 410. The plurality of projections 414 along the carriage410 provide multiple locking interfaces with the rack 418 to generate astrong locking force between the carriage 410 and the rack 418 of thesupport member 400 to securely retain the deflectable distal tip 104 ina deflected or straight orientation (FIGS. 1A, B, C). Optionally, thebrake portions 412, 416 include other features adapted to lock thecarriage assembly 406 in a desired position and thereby retain thedeflectable distal tip in a desired orientation. In one example, thebrake portions 412, 416 include a high friction surface such as a tackysubstrate (e.g., rubber) or a contact adhesive. In another example, thebrake portions 412, 416 include a high friction surface having aroughened substrate including, but not limited to, pitting, knurling andthe like.

The brake portion 412 of the carriage 410 is shown engaged with thebrake portion 416 of the support member 400 in FIG. 4. A biasing member420, such as a spring, elastomeric material and the like is coupled withthe carriage 410 and biases the carriage 410 toward the support member400 and into engagement thereon. In one option, the biasing member 420is a leaf spring coupled to the carriage 410 and extending between thecarriage and the handle assembly 150. The biasing member 420 isconstructed with, but not limited to, plastics, metals (e.g., stainlesssteel) and the like. The biasing member 420 is slidably coupled with thehandle assembly 150 along a path 422, in another option. The biasingmember 420 moves with the carriage assembly 406 along the path 422 andcontinually biases the carriage 410 including the brake portion 412toward the support member 400 and into locking engagement with the brakeportion 416. The biasing member 420 thereby ensures the carriageassembly 406 is locked in a desired position to locking the deflectabledistal tip 104 (FIGS. 1A, B, C and 2) in a desired orientation.

Referring now to FIG. 6, the carriage assembly 406 includes a retainer600 moveably coupled with the carriage 410 and the support member 400.In one option, the retainer 600 is constructed with plastics, metals andthe like. In one example, the retainer 600 is constructed with ULTEM aregistered trademark of the General Electric Company. The retainer 600is coupled with the flexible element 120 and transmits longitudinalmovement of the carriage assembly 406 along the handle assembly 150(FIG. 4) to the flexible element 120 thereby deflecting the distal tip104 (FIGS. 1A, B, C). In another option, the retainer 600 is sized andshaped to slidably couple along the support member 400 coupled with thehandle assembly 150. The retainer 600 moves in a proximal direction 602and a distal direction 604 along the support member 400 thereby applyingtension and compression, respectively to the flexible element 120 anddeflecting the distal tip 104. The support member 400 is retained withinthe handle assembly 150, as described above with ribs 402 (FIG. 4). Theribs 402, optionally extend into recesses 601 of the support member 400to substantially prevent movement of the support member 400 and catheterbody relative to the handle assembly 150.

In another option, the retainer 600 is moved in the proximal and distaldirections 602, 604 (i.e., longitudinally along the handle assembly 150)through movement of the carriage 410 coupled with the retainer 600. Atleast one of the carriage 410 and the retainer 600 includes a flange,such as flanges 606, sized and shaped to engage with the other of thecarriage 410 and the retainer 600. As shown in FIG. 6, the flanges 606extend from the retainer 410 and are engaged with the carriage 410 totransmit longitudinal movement of the carriage 410 to the retainer 600and the flexible element 120 (FIG. 4) coupled thereto. The flanges 606are slidably coupled with portions of the carriage 410 including struts608, shown in FIGS. 5 and 6. The struts 608 extend around the supportmember 400 from a base 610 of the carriage 410 and ensure the brakeportion 412 is adjacent to the brake portion 416 of the support member400 during movement of the carriage assembly 406 (FIG. 4). Referringagain to FIG. 6, the struts 608 and flanges 606 cooperate to permitlateral movement of the carriage 410 relative to, for instance, theretainer 600, support member 400 and the flexible element 120 whiletransmitting longitudinal movement to the retainer 600 to deflect thedistal end 104 (FIGS. 1A, B, C). As shown in FIG. 6, the carriage 410 isslidably coupled to the retainer 600 and moveable in a first direction612 and a second direction 614.

Referring again to FIGS. 4 and 6, the struts 608 of the carriage 410 arecoupled with the actuator 304. The actuator 304 is movablelongitudinally along the handle assembly 150 (as described above) andalso moveably laterally with respect to the handle assembly whendepressed (e.g., in the directions 612, 614 shown in FIG. 6). Becausethe actuator 304 is coupled with the carriage 410, lateral movement ofthe actuator 304 correspondingly moves the carriage 410 laterally. Asshown in FIGS. 3 and 4, the handle assembly 150 includes, in one option,a depression 314 sized and shaped to receive the actuator 304 when theactuator is depressed from the position shown in FIG. 4 to contact thehandle assembly 150 along the trough 424 of the depression 314.

As shown in FIG. 4, depression of the actuator 304 correspondinglydepresses the carriage 410 coupled thereto and disengages the brakeportion 412 of the carriage from the brake portion 416 of the supportmember 400 (e.g., the projections 414 of the carriage disengage from therack 418 of the support member). In one option, depression of theactuator 304 overcomes the restoring force of the biasing member 420 andmoves the carriage brake portion 412 away from the support member brakeportion 416. Disengaging the brake portions 412, 416 unlocks thecarriage assembly 406 and allows movement of the assembly 406 along thehandle assembly 150. As shown in FIG. 6, the carriage assembly 406(coupled with the actuator 304 shown in FIG. 4) is longitudinally movedin the directions 602, 604 to move the carriage 410 and correspondinglymove the retainer 600 coupled to the carriage 410, as described above.The flexible element 120 coupled with the retainer 600 is placed intension and/or compression when the carriage assembly 406 islongitudinally moved and the flexible element 120 deflects thedeflectable distal tip 104 (FIGS. 1A, B, C). The distal tip 104 deflectsaccording to the distance the actuator 304 and the carriage assembly 406of the steering and locking system 401 are moved. The deflectable distaltip 104 thereby deflects into a range of disparate orientationsaccording to the movement of the actuator 304. In another option, theactuator 304 is continually depressed to allow longitudinal movement ofthe carriage assembly 406. When the deflectable distal tip 104 isdeflected into a desired orientation, the actuator 304 is released(i.e., no longer depressed) and the biasing member 420 biases thecarriage 410 including the brake portion 412 into engagement with thebrake portion 416 of the support member 400. Engagement of the brakeportions 412, 416 (e.g., interlocking between the projections 414 andthe rack 418) locks the carriage assembly 406 along the support member400 and the handle assembly 150 thereby locking the deflectable distaltip 104 in the desired orientation. Optionally, the biasing member 420provides sufficient restoring force to the carriage 410 to move thebrake portions 412, 416 into engagement thereby allowing the brakeportions to generate the locking force needed retain the distal tip 104in the desired orientation.

Engagement of the brake portions 412, 416 (e.g., interlocking of theprojections 414 with the rack 418) of the steering and locking system401, as described above, ensures the deflectable distal tip 104 islocked in the desired orientation automatically with the release of theactuator 304. In any orientation achieved with the actuator 304 andcarriage assembly 406, the deflectable distal tip 104 is held in thatorientation by the engagement between the carriage assembly 406 and thesupport member 400 once the actuator 304 is released. Additionalactuation of separate locking mechanisms is therefore not needed. Thecarriage assembly 406 and the support member 400, as described above,thereby combine deflection and locking of the distal tip 104 in adesired orientation into a single mechanism, such as the steering andlocking system 401 using a single actuator (e.g., actuator 304).

In another option, the steering and locking system 401 includes a guide,such as the carriage guide 700, shown in FIG. 7. The carriage guide 700,in one option, is coupled with the support member 400. As shown in FIG.7, the carriage guide 700 includes alignment openings 702 sized andshaped to couple with the support member 400 and align the carriageguide 700 with the support member 400. In one option, shown in FIG. 6,the support member 400 includes fasteners, such as claws 616 sized andshaped to snap into engagement with corresponding features (e.g.,recesses) in the alignment openings 702 when the carriage guide 700 iscoupled with the support member 400. In another option, the carriageguide 700 is coupled with the support member 400 with adhesives, screws,bolts, pins, clamps and the like. The carriage guide 700 is constructed,optionally, with plastics, metals and the like. In one example, thecarriage guide 700 includes nylon.

Referring again to FIG. 7, the carriage guide 700 includes at least onetrack 704 sized and shaped to slidably couple the strut 608 of thecarriage 410 with the guide 700. As shown in FIG. 7, the carriage guide700 includes two tracks 704. The tracks 704 and struts 608 are sized andshaped to permit longitudinal movement of the carriage 410 along thehandle assembly 150 (FIG. 4). In one example, the carriage guide 700permits movement of the carriage 410 in the directions 602, 604.Additionally, the carriage guide 700 is sized and shaped to allowlateral movement of the carriage 410 with respect to the handle assembly150 and the support member 400. As described above, the carriage 410moves laterally (e.g., in the directions 612, 614) to disengage thefirst brake portion 412 of the carriage 410 from the second brakeportion 416 of the support member 400. The struts 608 slide laterallywithin the tracks 704 to move the brake portion 412 of the carriage 410laterally relative to the support member 400.

In another option, the retainer 600 is captured between the supportmember 400 and the carriage guide 700. As shown in FIG. 7, the retainer600 is slidably coupled between the carriage guide 700 and the supportmember 400 and moveable in the directions 602, 604 (i.e., longitudinallyalong the handle assembly 150 shown in FIG. 4). Optionally, the flanges606 of the retainer 600 extend at least part way through the tracks 704and are sized and shaped to slidably couple with the carriage guide 700.The tracks 704 cooperate with the flanges 606 to thereby guide theretainer 600 along the support member 400 and the carriage guide 700when the retainer 600 is longitudinally moved. Additionally, thecarriage guide 700 and the support member 400 are sized and shaped tosubstantially constrain the retainer 600 from moving laterally in thedirections 612, 614 while permitting longitudinal movement. As shown inFIG. 7, the carriage guide 700 and the support member 400 are disposedover and under the retainer 600, respectively. In one option, theretainer 600 is substantially laterally static with respect to theflexible element 120 (FIG. 4), the support member 400, and the handleassembly 150 (FIG. 4).

As shown in FIG. 7, the carriage guide 700 and the support member 400cooperate to allow movement of the carriage assembly 406 (e.g., thecarriage 410 and the retainer 600) longitudinally along the supportmember 400 and handle assembly 150 and thereby permit deflection of thedistal tip 104 (FIGS. 1A, B, C and 2) through tension and compression ofthe flexible element 120 (FIG. 4). Moreover, the carriage guide 700 andthe support member 400 cooperate to permit lateral movement of thecarriage 410 and substantially prevent lateral movement of the retainer600, as described above. Optionally, the carriage guide 700 has guidefeatures including rails, grooves, channels and the like sized andshaped to permit movement of the carriage assembly 406 in thelongitudinal direction and substantially prevent lateral movement of theretainer 600.

FIG. 8 is a perspective view of a portion of the steering and lockingsystem 401 including the carriage assembly 406 coupled around theproximal end 102 of the catheter body 110. The carriage assembly 406 isshown coupled with a tube assembly 800. In one option, the tube assembly800 is coupled with the retainer 600. The tube assembly 800 is coupledaround the flexible element 120 and has an inner diameter slightlylarger than the outer diameter of the flexible element 120, in anotheroption. The tube assembly 800 thereby provides support to the flexibleelement 120 and constrains the flexible element 120 from movinglaterally and substantially prevents buckling of the flexible element120. The support against buckling provided by the tube assembly 800allows loading of the flexible element 120 in compression to permitpushing of the flexible element 120 and deflection of the distal tip 104(FIGS. 1A, B, C and 2) in an opposing direction to deflection caused bytension. Optionally, the tube assembly 800 extends between the retainer600 and the sidewall exit 403 (FIG. 4) of the flexible element 120 toprovide support therebetween. The flexible element 120 is therebyconstrained from moving laterally by the tube assembly 800 between theretainer 600 and sidewall exit 403, and the sidewall 124 (FIG. 2)between the sidewall exit 403 and the distal tip 104.

FIG. 9, is a perspective view of the proximal end 102 of the catheterbody 110 and one example of the tube assembly 800 without the carriageassembly 406 (FIG. 8) coupled thereto for clarity. As shown in FIG. 9,in one option, the tube assembly 800 includes a first tube 900 slidablycoupled with a second tube 902 both of which are coupled around theflexible element 120. The first tube 900 has an inner diameter slightlylarger than the outer diameter of the flexible element 120 andconstrains the flexible element 120 from moving laterally (e.g.,buckling), as described above. The first tube 900 is coupled with theretainer 600 (FIGS. 6 and 8), optionally, and moves with the retainer600 and the flexible element 120 when the carriage assembly 406 is movedlongitudinally along the handle assembly 150 (FIG. 4), as describedabove.

The second tube 902 has an inner diameter slightly larger than the outerdiameter of the first tube 900 to permit sliding movement between thetubes 900, 902 throughout a range of travel of the carriage assembly 406in the handle assembly 150. The second tube 902 substantially preventslateral movement of the first tube 900 because of the tight tolerancesbetween inner diameter and outer diameter of the respective tubes 900,902. The first tube 900 extends through a portion of the second tube902. The second tube 902 has a sufficiently small inner diameter tosubstantially prevent buckling of the flexible element 120 where theelement 120 exits the first tube 900 and is received within the secondtube 902. As shown in FIG. 9, the second tube has a curved portion 904,in another option. The small inner diameter of the second tube 902constrains the flexible element 120 and permits movement of the element120 through the curved portion 904 according to the path defined by theinner diameter of the second tube 902 in the portion 904.

The first and second tubes 900, 902, as described above, therebysubstantially prevent lateral movement and buckling of the flexibleelement 120. The first and second tube 900, 902 allow loading of theflexible element 120 in compression to permit deflection of the distaltip 104 (FIGS. 1A, B, C and 2) through pushing of the flexible element120. In yet another option, the second tube 902 is coupled along thecatheter body 110, for instance with a flexible element guide (describedbelow), and is therefore static relative to movement of the carriageassembly 406 (FIG. 8). The first tube 900 is coupled with the retainer600 of the carriage assembly 406, as described below. Longitudinalmovement of the carriage assembly 406 correspondingly moves the flexibleelement 120 and the first tube 900 coupled therearound with respect tothe second tube 902. Because of the slidable coupling between the firstand second tubes 902, the flexible element 120 is supported throughoutthe range of travel of the carriage assembly 406 along the handleassembly 150. Optionally, the tube assembly 800 includes a portion ofthe handle assembly 150 sized and shaped to slidably couple with thefirst tube 900. For instance, the handle assembly 150 is molded,machined and the like to slidably couple with the first tube 900 in asimilar manner as the second tube 902. The handle assembly 150 therebycooperates with the first tube 900 to substantially prevent lateralmovement of the flexible element 120 including buckling. One example ofa tube assembly sized and shaped to constrain lateral movement is shownin Pudelko et al., U.S. patent application Ser. No. 10/670,150, filed onSep. 24, 2003, entitled “BI-DIRECTIONAL CATHETER ASSEMBLY AND METHODTHEREFOR,” which is assigned to the assignee of the present applicationand incorporated by reference herein in its entirety.

FIG. 10 shows the retainer 600, the first tube 900 of the tube assembly800 coupled with the retainer 600 and the retaining pin 408. As shown inFIG. 10, the retaining pin 408 includes a neck 1000 and a head 1002. Theneck 1000, in one option, has an outer perimeter slightly larger thanthe inner perimeter of a pin opening 1004 of the retainer 600. The neck1000 creates an interference fit with the retainer 600 when theretaining pin 408 is placed in the pin opening 1004 thereby securelyfastening the retaining pin 408 to the retainer 600. The tube 900, inanother option, extends through a slot 1006 of the retainer 600 andaround the neck 1000 of the retaining pin 408. The head 1002 extendsover at least a portion of the tube 900 to substantially prevent lateralmovement of the tube 900 out of the slot 1006. As described above, theflexible element 120 extends through the tube 900. As shown in FIG. 10,the flexible element 120 extends with the tube 900 through the retainer600. The flexible element 120 and the tube 900 extend proximally fromthe retainer 600 and provide corresponding free ends 1008, 1010. Thetube 900 is coupled with the flexible element 120, for instance, bycrimping the free end 1010 of the tube 900 around the free end 1008 ofthe flexible element 120. The tube 900 grasps the flexible element 120and thereby immobilizes the flexible element 120 within the tube 900. Inyet another option, the tube 900 is coupled with the flexible element120 with a weld, adhesives, mechanical fasteners and the like.

In one option, the tube 900 includes a non-linear portion, such as acurved portion 1012 sized and shaped to wrap around at least a portionof the neck 1000 of the retaining pin 408. In another option, thenon-linear portion includes, but is not limited to, spiraled, zig-zag,serpentine geometries and the like. The slot 1006 of the retainer 600includes a non-linear portion, such as a curved slot portion 1014,having a similar geometry to the curved portion 1012 of the tube 900.The curved portion 1012 of the tube 900 is coupled between the retainingpin 408 and the retainer 600 within the curved slot portion 1014. Theengagement of the curved portion 1012 with retaining pin 408 and theretainer 600 in the curved slot portion 1014 substantially preventslongitudinal movement of the tube 900 with respect to the retainer 600.The tube 900 is locked in place within the retainer 600 by the curvedportion 1012. In another option, where the tube 900 is coupled with theflexible element 120 (e.g., by crimping as described above), theflexible element 120 is substantially prevented from movinglongitudinally with respect to the retainer 600. Longitudinal movementof the carriage assembly 400 (FIG. 4), including the retainer 600,thereby moves the tube 900 and the flexible element 120 to deflect thedistal tip 104, as described above.

Referring again to FIGS. 7-9, a portion of the carriage assembly 406 ofthe steering and locking system 401, such as the retainer 600, isconstrained from moving laterally (e.g., in the directions 612, 614), asdescribed above. The carriage guide 700 and the support member 400cooperate, in one option, to constrain lateral movement of the retainer600 while allowing longitudinal movement of the carriage assembly 406along the handle assembly 150 (FIG. 4). The laterally static retainer600 cooperates with the tube assembly 800, shown in FIGS. 8 and 9, tosubstantially prevent lateral movement of the flexible element 120during longitudinal movement of the carriage assembly 120 to causedeflection in the distal tip 104 of the catheter body 110 (FIGS. 1A, B,C). Because the flexible element 120 is substantially prevented frommoving laterally (e.g., buckling) with respect to the handle assembly150, the flexible element 120 is loadable in compression to deflect thedistal tip 104 in an opposed direction to the deflection caused withtensioning of the flexible element. In another option, the carriageassembly 406 is moveable in the proximal and distal directions 602, 604to pull and push the flexible element 120 and thereby deflect the distaltip 10 in opposed directions. The cooperation of the retainer 600 andthe tube assembly 800 permits active deflection of the distal tip 104with compression of the flexible element 120 from deflected positions,such as the positions shown in FIGS. 1A, C. The passive deflectionprovided by the natural elasticity of the catheter body 110 and/orengagement of the catheter body 110 with surfaces such as vasculature isthereby unnecessary for control of the deflectable distal tip 104.Instead, the steering and locking system 401 actively controlsdeflection of the distal tip 104 in any direction according to movementof the carriage assembly 406.

As shown in FIGS. 7-9, in another option, the retainer 600 and the tubeassembly 800 cooperate to substantially prevent lateral movement of theflexible element 120 and allow for tension and compression of theflexible element 120 while the carriage 410 is permitted to movelaterally to engage and disengage the brake portions 412, 416 andcorrespondingly lock and unlock to retain the deflectable distal tip 104in a desired orientation. The steering and locking system 401 (e.g., thecarriage assembly 406 and the support member 400) thereby deflects thedistal tip 104 with tension and compression of the flexible element 120,and locks the distal tip 104 in an orientation through engagement of thebrake portions 412, 416. Deflection of the distal tip 104 and locking ofthe tip 104 in a desired orientation are consolidated into a singleassembly, the steering and locking system 401. Additionally, thesteering and locking system 401 is operated with a single control, theactuator 304 (FIGS. 3 and 8) to deflect the distal tip 104 and lock thetip in the desired orientation.

FIGS. 11A, B show another example of the steering and locking system 401including the retainer 600 and the support member 400 (only a portion ofthe support member 400 is shown in FIGS. 11A, B for clarity) coupledalong the catheter body 110. In one option, the catheter body 110includes a flexible element guide 1100 sized and shaped to couple aroundthe catheter body 110 at the sidewall exit 403 (FIG. 4). The flexibleelement guide 1100 extends away from the catheter body 110. Optionally,the flexible element guide 1100 couples with the second tube 902 (FIG.9) and retains the second tube 902 along the catheter body 110. Theflexible element guide 1100 is constructed with, but not limited to,plastics, metals and the like. In one example, the retainer 600 isconstructed with PEBAX.

In another option, the support member 400 includes a proximal stop 1102extending from the support member 400. The proximal stop 1102, in yetanother option, is proximal to the brake portion 416 (e.g., the rack418). The retainer 600 moves along the handle assembly 150 (FIG. 4) andthe support member 400, as described above. The flexible element guide1100 and the proximal stop 1102 are sized and shaped to engage with theretainer 600 and substantially prevent movement of the retainer 600proximal to the proximal stop 1102 and distal to the flexible elementguide 1100. The flexible element guide 1100 and the proximal stop 1102thereby define a range of travel for the retainer 600. As describedabove, the retainer 600 is coupled with the carriage 410 (FIG. 4) andmoves longitudinally with the carriage 410. The range of travel definedby the flexible element guide 1100 and the proximal stop 1102 is therebyalso the range of travel for the carriage 410. Actuation of the carriageassembly 406 (e.g., the carriage 410 and the retainer 600) through theactuator 304 (FIGS. 3 and 4) is limited to the range of travel definedby the flexible element guide 100 and the proximal stop 1102.

A first range of travel 1104A is shown in FIG. 11A between the flexibleelement guide 1100 and the proximal stop 1102. The retainer 600 is freeto move longitudinally between the guide 1100 and the stop 1102 (i.e.,through the range of travel 1104A) and thereby deflect the distal tip104 (FIGS. 1A, B, C) through corresponding compression and tension ofthe flexible element 120 (FIGS. 2 and 4). A second range of travel 1104Bis shown in FIG. 11B. Like the first range of travel 1104A, the retainer600 is moveable between the flexible element guide 1100 and the proximalstop 1102. However, the second range of travel 1104B is shorter than thefirst range of travel 1104A because the support member 400 including theproximal stop 1102 is coupled closer to the flexible element guide 1100.Conversely, the support member 400 and the proximal stop 1102 arecoupled more proximally relative to the flexible element guide 1100 toprovide the longer first range of travel 1104A. A variety of ranges oftravel are thereby available by changing the location the support member400 couples around the catheter body 110. In one option, once thesupport member 400 is coupled around the catheter body 110 both arepositioned within a handle assembly 150 adapted to couple with thesupport member 400 as described above. Optionally, the handle assembly150 is a standard handle design usable with a variety of configurationsof the support member 400 and the catheter body 110 to define acorresponding variety of ranges of travel (e.g., ranges of travel 1104A,B). Coupling the support member 400 with the handle assembly 150 allowsfor the variety of ranges of travel while still using a single handledesign.

In one option, the longer range of travel 1104A (FIG. 11A) is used withthe catheter body 110 having a deflectable distal tip 104 (FIGS. 1A, B,C) with a large range of deflection. The longer range of travel 1104Apermits full use of the distal tip 104 deflection range. In anotheroption, the longer range of travel 1104A is used with a catheter body110 that is relatively rigid (e.g., formed with a stiff material orhaving a larger diameter). The longer range of travel 1104A permits thecarriage assembly 406 (FIG. 4) to pull and push the flexible element 120a sufficient amount to deflect the rigid distal tip 104 into a desiredorientation. Optionally, the shorter range of deflection 1104B (FIG.11B) is used with a catheter body 110 constructed with a relativelyflexible material so that only a small range of motion is needed for thecarriage assembly 406 to deflect the distal tip 104 through a desiredrange of deflected orientations. In yet another option, the deflectabledistal tip 104 needs only a limited range of deflection and the shorterrange of travel 1104B provided by the proximal stop 1102 and theflexible element guide 1100 ensures the carriage assembly 406 will onlydeflect the distal tip 104 within that desired deflection range. Theranges of travel 1104A, B are only two examples of the range of travelavailable by coupling the support member 400 at different locationsalong the catheter body 110. A variety of ranges of travel are availablewhere the proximal stop 1102 of the support member 400 is coupledproximally further and distally closer to the flexible element guide1100.

Referring again to FIGS. 11A, B, in another option, the support member400 is coupled along the catheter body 110 at a predetermined locationto establish neutral home positions 1106A, B along the support member400 within the ranges of travel 1104A, B, respectively for the carriageassembly 406 (FIG. 4) including the retainer 600. In yet another option,the length of the flexible element 120 (FIG. 4) cooperates with theposition of the support member 400 to determine the home positions1106A, B. The home positions 1106A, B provide a corresponding neutral(straight) orientation of the distal tip 104 shown in FIG. 1B,optionally.

As shown in FIG. 11A, the home position 1106A is near the flexibleelement guide 1100 and remote from the proximal stop 1102. The carriageassembly 406, including the retainer 600, is thereby able to move arelatively small distance distally and a relatively large distanceproximally. The deflectable distal tip 104 of the catheter assembly 100with this range of travel 1104A and home position 1106A is able todeflect in a first direction, for instance as shown in FIG. 1C, and ableto deflect a larger amount in a second direction, for instance up to atleast the orientation shown in FIG. 1A. As shown in FIG. 11B, thesupport member 400 is coupled with the catheter body 110 so the homeposition 1106B is positioned more equidistantly between the flexibleelement guide 1100 and the proximal stop 1102 than with the homeposition 1106A shown in FIG. 6. In still another option, the length ofthe flexible element 120 cooperates with the position of the supportmember 400 on the catheter body 110 to provide the home position 1106B.The deflectable distal tip 104 of the catheter assembly 100 with thisrange of travel 1104B and home position 1106B is able to move at leastbetween the orientation shown in FIG. 1C and an orientation betweenthose shown in FIGS. 1A and 1B.

Referring again to FIG. 4, in operation, the actuator 304 is depressedinto or toward the depression 314. Movement of the actuator 304laterally correspondingly moves the carriage 410 of the steering andlocking system 401 laterally with respect to the flexible element 120and the handle assembly 150. Depressing the actuator 304 overcomes therestoring force of the biasing device 420 adapted to engage the firstbrake portion 412 of the carriage 410 with the second brake portion 416of the support member 400. The first brake portion 412 including, in oneoption, the projections 414 is thereby disengaged from the second brakeportion 416 to permit longitudinal movement of the carriage assembly 406(including the carriage 410 and the retainer 600 shown in FIG. 6) alongthe handle assembly 150 and the support member 400. Movement of thecarriage assembly 406 correspondingly moves the flexible element 120coupled thereon. The flexible element 120 is loaded in compressionand/or tension as desired with respective distal and proximal movementof the carriage assembly 406. In another option, compression of theflexible element 120 deflects the distal tip 104 into the orientationshown in FIG. 1C. In yet another option, tension of the flexible element120 deflects the distal tip 104 into the orientation shown in FIG. 1A.When a desired orientation of the deflectable distal tip 104 isobtained, including a straight orientation as shown in FIG. 1B, theactuator 304 is released allowing the biasing member 420 to push thecarriage 410 and the first brake portion 412 into engagement with thesecond brake portion 416 of the support member 400. Optionally,engagement of the projections 414 with the rack 418 creates aninterlocking fit therebetween that substantially prevents movement ofthe carriage assembly 406 along the handle assembly 150. In stillanother option, a biasing member 420 providing a relatively weakrestoring force is used to bias the carriage assembly 406 because theprojections 414 and the rack 418 lock the carriage assembly 406 in placeonce engaged. The steering and locking system 401 including the carriageassembly 406 and the support member 400 thereby provides steering andlocking functions with a single assembly using a single actuator 304.

Referring now to FIGS. 6-9, the retainer 600 of the carriage assembly406 is sized and shaped to permit lateral movement of the carriage 410relative to the flexible element 120 (FIG. 4) while the retainer 600remains laterally static. In one option, the retainer 600 includesflanges 606 that transmit longitudinal movement of the carriage 410 tothe retainer 600 and allow sliding lateral movement of the carriage 410with respect to the retainer 600. As shown in FIG. 7, optionally, thecarriage guide 700 is coupled over the retainer 600 and the retainer 600is slidably coupled between the carriage guide 700 and the supportmember 400. The carriage guide 700 and the support member 400 cooperateto substantially prevent lateral movement of the retainer 600 (e.g.,movement in the directions 612, 614). The retainer 600 thereby retainsthe flexible element 120 in substantially laterally static positionwhile the carriage assembly 406 moves longitudinally (e.g., indirections 602, 604) along the handle assembly 150 (FIG. 4) and thesupport member 400. The moveable coupling between the carriage 410 andthe retainer 600 allows the first and second brake portions 412, 416 toengage with lateral movement of the carriage 410 and thereby lock thecarriage assembly 406 along the support member 400 in the handleassembly 150 without laterally moving the retainer 600.

In another option, the retainer 600 cooperates with the tube assembly800 shown in FIGS. 8 and 9 to substantially prevent lateral movement ofthe flexible element 120 when the element 120 is loaded in tension andcompression (e.g., moved in the directions 602, 604 shown in FIG. 6).The first and second tubes 900, 902, optionally, have inner diametersslightly larger than the outer diameter of the flexible element 120 toconstrain movement of the flexible element and substantially preventbuckling when the element 120 is loaded in compression. The carriageassembly 406 (FIG. 6) is thereby moveable in the directions 602, 604 topull and push the flexible element 120 and correspondingly deflect thedistal tip 104 into at least the orientations shown in FIGS. 1A, B, C.Additionally, the retainer 600 and the tube assembly 800 cooperate toallow active deflection of the distal tip 104 through compression andtension of the flexible element without requiring passive deflectionprovide by the natural elasticity of the catheter body 110 (FIGS. 1A, B,C) and/or engagement with vasculature surrounding the catheter body 110.

FIG. 12 is a block diagram showing one example of a method 1200 formaking a deflectable catheter assembly. At 1202, a flexible element iscoupled to a deflectable distal tip of a catheter shaft. At 1204 asupport member is coupled around a proximal portion of the cathetershaft. The support member includes a first brake portion, such as arack, high friction surface and the like, extending along at least aportion of the support member. At 1206, a handle is coupled to thesupport member. In one option, the handle is coupled around a hemostasisvalve, and the hemostasis valve is in communication with a deliverylumen of the catheter shaft. At 1208, a carriage assembly is moveablycoupled with the handle. The carriage assembly includes a carriagehaving a second brake portion (e.g., projection, high friction surfaceand the like) sized and shaped to engage with at least a portion of thefirst brake portion. At 1210, a flexible element is coupled with thecarriage assembly. At 1212, a biasing device is coupled between thecarriage assembly and the handle. The biasing device is moveably coupledalong the handle, and is adapted to bias the second brake portion intoengagement with the first brake portion. Optionally, the method 1200includes coupling an actuator with the carriage. The actuator is adaptedto move the carriage between a first position where the second brakeportion is engaged with the first brake portion and a second positionwhere the second brake portion is disengaged with the first brakeportion.

In one option, the method 1200 includes coupling a flexible elementguide with the catheter shaft. The flexible element extends outside ofthe catheter shaft at the flexible element guide. Coupling the supportmember around the proximal portion of the catheter shaft includes, inanother option, coupling the support member around the proximal portionof the catheter shaft, and the support member includes a proximal stopproximal to the first brake portion. The carriage assembly has a rangeof travel along the handle between the flexible element guide and theproximal stop. Optionally, the method 1200 includes coupling the supportmember around a predetermined location of the catheter shaft to definethe range of travel.

In another option, moveably coupling the carriage assembly with thehandle includes slidably coupling a retainer with the carriage, and theflexible element is coupled with the retainer. The retainer is sized andshaped to move with the carriage longitudinally along the handle, andthe retainer is sized and shaped to remain substantially laterallystatic relative to the flexible element. Optionally, the method 1200includes slidably coupling a carriage guide with the carriage assembly,and the carriage guide is sized and shaped to permit lateral movement ofthe carriage relative to the flexible element and substantially preventlateral movement of the retainer. The carriage guide is sized and shapedto permit movement of the carriage assembly longitudinally along thehandle.

Optionally, the method 1200 includes moving the carriage laterallyrelative to the flexible element, and disengaging the second brakeportion from the first brake portion. The carriage assembly is movedlongitudinally along the handle and the flexible element moves with thecarriage assembly and pulls or pushes the deflectable distal tip. Theflexible element deflects the deflectable distal tip between a firstorientation and a second orientation. The method 1200 further includesretaining the deflectable distal tip in the second orientation when thebiasing device moves the second brake portion into engagement with thefirst brake portion.

The above described deflectable catheter provides a steering and lockingsystem capable of locking the deflectable distal tip in a desireddeflected position. The carriage and retainer cooperate with the supportmember to longitudinally move the flexible element to deflect the distaltip and lock the distal tip in a desired deflected position. Thesteering and locking system substantially prevents movement of thecarriage proximally or distally, thereby substantially preventingfurther undesired deflection of the catheter or straightening when thecarriage is in the locked position. Optionally, the steering and lockingsystem automatically locks the catheter in a desired orientation byreleasing the actuator. In one option, the carriage includes the secondbrake portion having, for instance, multiple projections that provide astrong locking force between the carriage and the first brake portion(e.g., rack, high friction surface and the like) of the support memberto securely retain the distal tip of the catheter in a deflectedorientation.

As described above, the carriage assembly including the carriage andretainer are operated to deflect the distal tip and lock the distal tipin a desired deflected position. The carriage assembly therebyconsolidates the deflection system with the locking system into thesingle steering and locking system to simplify use of the catheter. Inanother option, a single actuator is used to control both the deflectionand locking of the deflectable catheter. Additional controls and thelike are unnecessary. Further, combining the deflection and lockingfeatures decreases labor and manufacturing costs. Moreover, in anotheroption, the catheter handle includes a hemostasis valve and/or flushport therein to further simplify use of the deflectable catheter.

Additionally, the support member provides a brake portion for lockingthe carriage in place and is a structural support to the catheter shaftduring deflection and traversing of the vasculature. Moreover, thesupport member is coupled along the catheter shaft at a predeterminedlocation to provide a range of travel for the carriage, and thereby arange of deflection of the distal tip. The space between the proximalstop of the support member and the flexible element guide along thecatheter shaft defines the range of travel and corresponding range ofdeflection for the distal tip. Coupling the support member distallytoward the flexible element guide provides a short range of travel(e.g., for thin walled catheters). Coupling the support memberproximally away from the flexible element guide provides a longer rangeof travel (e.g., for thicker catheters, greater deflection ranges, andthe like). Further, coupling the support member at the predeterminedlocation also establishes a neutral position for the carriage where thedeflectable distal tip assumes an undeflected orientation. The supportmember is coupled along the catheter body at a variety of locations todefine a corresponding variety of ranges of travel. In yet anotheroption, the support member is coupled with a standard handle sized andshaped to receive the support member. A single handle is thereby usedwith the same support member no matter what the range of travel is ofthe carriage assembly thereby decreasing labor and manufacturing costs.

Further, the retainer and tube assembly substantially prevent bucklingof the flexible element thereby allowing tension and compression loadingof the flexible element. Because the flexible element is constrainedfrom moving laterally between the retainer and the deflectable distaltip the element is loadable in tension and compression to providebidirectional deflection of the distal tip. In another option, loadingthe flexible element in compression permits active straightening of thedeflected catheter thereby providing active control for deflection andstraightening with the carriage assembly (i.e., the natural catheterelasticity does not unpredictably control straightening of the distaltip). The carriage guide, in yet another option, facilitateslongitudinal movement of the carriage and the retainer while holding theretainer in a substantially laterally static position with respect tothe flexible element. The carriage guide thereby ensures the retainercooperates with the tube assembly to keep the flexible element static,while permitting longitudinal movement of the carriage assembly fordeflection of the distal tip. Additionally, the carriage guide permitslateral movement of the carriage to engage and disengage the secondbrake portion of the carriage with the first brake portion of thesupport member.

It is to be understood that the above description is intended to beillustrative, and not restrictive. Many other embodiments will beapparent to those of skill in the art upon reading and understanding theabove description. It should be noted that embodiments discussed indifferent portions of the description or referred to in differentdrawings can be combined to form additional embodiments of the presentapplication. The scope of the invention should, therefore, be determinedwith reference to the appended claims, along with the full scope ofequivalents to which such claims are entitled.

1. A deflectable catheter comprising: a catheter shaft including adeflectable distal tip; a support member coupled around a proximalportion of the catheter shaft, wherein the support member includes afirst brake portion extending along at least a portion of the supportmember; a handle coupled around the support member; a carriage moveablycoupled along the handle, wherein the carriage includes a second brakeportion sized and shaped to engage with at least a portion of the firstbrake portion and substantially prevent movement of the carriagerelative to the handle; a flexible element coupled between thedeflectable distal tip and the carriage; and a biasing device coupledbetween the carriage and the handle, and the biasing device is adaptedto bias the second brake portion into engagement with the first brakeportion.
 2. The deflectable catheter of claim 1, wherein the cathetershaft includes a flexible element guide wherein the flexible elementextends outside of the catheter shaft at the flexible element guide. 3.The deflectable catheter of claim 2, wherein the support member includesa proximal stop proximal to the first brake portion.
 4. The deflectablecatheter of claim 3, wherein the carriage has a range of travel betweenthe flexible element guide and the proximal stop, and the support memberis coupled around a predetermined location of the catheter shaft todefine the range of travel.
 5. The deflectable catheter of claim 1,wherein the first brake portion and the second brake portion are sizedand shaped to substantially prevent movement of the carriage along thehandle when the second brake portion is engaged with the first brakeportion.
 6. The deflectable catheter of claim 1, wherein first brakeportion includes a rack and the second brake portion includes at leastone projection sized and shaped to engage with at least a portion of therack.
 7. The deflectable catheter of claim 1, further comprising acarriage guide slidably coupled with the carriage, wherein the carriageguide is sized and shaped to permit lateral movement of a portion of thecarriage and substantially prevent lateral movement of a second portionof the carriage, and the carriage guide is sized and shaped to permitlongitudinal movement of the carriage along the handle.
 8. Thedeflectable catheter of claim 1, wherein the carriage extends around atleast a portion of the support member.
 9. The deflectable catheter ofclaim 8, wherein the second brake portion extends along an interiorsurface of the carriage.
 10. The deflectable catheter of claim 1,wherein the biasing device includes a spring slidably coupled with thehandle.
 11. A deflectable catheter comprising: a catheter shaftincluding a deflectable distal tip; a flexible element coupled to thedeflectable distal tip; a handle; a first brake portion extending alongat least a portion of the handle; a carriage assembly moveably coupledwith the handle, wherein the carriage assembly includes a carriageincluding a second brake portion sized and shaped to engage with thefirst brake portion and substantially prevent movement of the carriagerelative to the handle, and a retainer coupled with the flexible elementand slidably coupled with the carriage, wherein the retainer is sizedand shaped to move with the carriage longitudinally along the handle,and the retainer is sized and shaped to remain substantially laterallystatic relative to the flexible element; and a biasing device coupledbetween the carriage and the handle, and the biasing device is adaptedto bias the first brake portion into engagement with the second brakeportion.
 12. The deflectable catheter of claim 11, wherein the firstbrake portion includes a rack and the second brake portion includes atleast one projection sized and shaped to engage with the rack.
 13. Thedeflectable catheter of claim 11, wherein the carriage is sized andshaped to move laterally with respect to the retainer between a firstposition where the second brake portion is engaged with the first brakeportion and a second position where the second brake portion isdisengaged with the first brake portion.
 14. The deflectable catheter ofclaim 11, further comprising a carriage guide slidably coupled with thecarriage assembly, and the carriage guide is sized and shaped to permitlateral movement of the carriage relative to the flexible element andsubstantially prevent lateral movement of the retainer, and the carriageguide is sized and shaped to permit movement of the carriage assemblyalong the handle.
 15. The deflectable catheter of claim 14, wherein thecarriage guide includes at least one track and the carriage includes atleast one strut sized and shaped to slidably couple with the carriageguide along the at least one track.
 16. The deflectable catheter ofclaim 14, wherein the retainer is slidably coupled between the carriageguide and the support member.
 17. The deflectable catheter of claim 14,wherein at least one of the retainer and the carriage includes at leastone flange, and the at least one flange is engaged against the retaineror the carriage, and the flange transmits longitudinal movement of thecarriage to the retainer and the flexible element.
 18. The deflectablecatheter of claim 11, further comprising a first tube coupled with theretainer and coupled around the flexible element, wherein the first tubesubstantially prevents lateral movement of the flexible element.
 19. Thedeflectable catheter of claim 18, further comprising a second tubeslidably coupled around the first tube and coupled with the cathetershaft, and the flexible element extends through the second tube towardthe deflectable distal tip.
 20. The deflectable catheter of claim 18,wherein the first tube includes a non-linear portion engaged with acorresponding non-linear portion of the retainer.
 21. The deflectablecatheter of claim 11, wherein the handle includes a hemostasis valve incommunication with a delivery lumen in the catheter shaft.
 22. A methodfor making a deflectable catheter comprising: coupling a flexibleelement to a deflectable distal tip of a catheter shaft; coupling asupport member around a proximal portion of the catheter shaft, whereinthe support member includes a first brake portion extending along atleast a portion of the support member; coupling a handle around thesupport member; moveably coupling a carriage assembly with the handle,wherein the carriage assembly includes a carriage having a second brakeportion shaped to engage with at least a portion of the first brakeportion; coupling the flexible element to the carriage assembly; andcoupling a biasing device between the carriage assembly and the handle,and the biasing device is adapted to bias the second brake portion intoengagement with the first brake portion.
 23. The method of claim 22,further comprising coupling a flexible element guide with the cathetershaft, and the flexible element extends outside of the catheter shaft atthe flexible element guide.
 24. The method of claim 23, wherein couplingthe support member around the proximal portion of the catheter shaftincludes coupling the support member around the proximal portion of thecatheter shaft, and the support member includes a proximal stop proximalto the first brake portion, and the carriage assembly has a range oftravel along the handle between the flexible element guide and theproximal stop.
 25. The method of claim 23, wherein coupling the supportmember around the proximal portion of the catheter shaft includescoupling the support member around a predetermined location of thecatheter shaft to define the range of travel.
 26. The method of claim22, wherein moveably coupling the carriage assembly with the handleincludes slidably coupling a retainer with the carriage, and theretainer is sized and shaped to move with the carriage longitudinallyalong the handle, and the retainer is sized and shaped to remainsubstantially laterally static relative to the flexible element, and theflexible element is coupled with the retainer.
 27. The method of claim26, further comprising slidably coupling a carriage guide with thecarriage assembly, and the carriage guide is sized and shaped to permitlateral movement of the carriage relative to the flexible element andsubstantially prevent lateral movement of the retainer, and the carriageguide is sized and shaped to permit movement of the carriage assemblylongitudinally along the handle.
 28. The method of claim 22, furthercomprising coupling an actuator with the carriage, and the actuator isadapted to move the carriage between a first position where the at leastone projection is engaged with the rack and a second position where theat least one projection is disengaged with the rack.
 29. The method ofclaim 22, further comprising coupling the handle around a hemostasisvalve, and the hemostasis valve is in communication with a deliverylumen of the catheter shaft.
 30. The method of claim 22, furthercomprising: moving the carriage laterally relative to the flexibleelement, disengaging the second brake portion from the first brakeportion; moving the carriage assembly longitudinally along the handle,wherein the flexible element moves with the carriage assembly and theflexible element pulls or pushes the deflectable distal tip; deflectingthe deflectable distal tip between a first orientation and a secondorientation; and retaining the deflectable distal tip in the secondorientation, wherein the biasing device moves the carriage and thesecond brake portion into engagement with the first brake portion.